The
Oldcorollas FAQ
An FAQ dealing with KE1x to KE7x Toyota Corollas
Supplement to http://groups.yahoo.com/groups/oldcorollas
K motors were designed to run on leaded petrol, which had a Research
Octane Number (RON) of about 95. Leaded petrol has been outlawed almost
everywhere in the world now, because it pollutes the environment and is
good for your motor but bad for you. Japan got rid of leaded fuel in
1972.
Leaded Replacement Petrol
As of 2002, all petrol pumps in Australia now flow LRP, or Leaded
Replacement Petrol. LRP is allegedly governed to be 95 RON.
Unleaded Petrol
Is it safe to use ULP in a K motor without valve additive?
----- Original Message -----
From: Gail Ryan (Gail.Ryan@toyota.com.au)
To: Super Jamie (jamie@superjamie.net)
Sent: Wednesday, July 24, 2002 10:09
AM
Subject: Product enquiry
Thank you for enquiry that has been
forwarded to the Toyota Customer
Relations Department.
With the information you have
supplied the 3K-H engine
production year 1966 - 1974. If this
vehicle was produced after Feb 1972
you may use unleaded petrol. And
there is no modification required.
Regards
Gail Ryan
So basially, yes, as long as it was made after 1972. If you like, you
can
squirt in the little 50c "Valve Master" or similar tube that petrol
stations sell, but I doubt it's necessary. Anyone who tries to get you
to spend thousands of dollars having hardened valve seats installed in
your motor is ripping you off. These cars have an aluminium head, by
design, they must have hardened steel valve seats or you'd drive around
the block once and your motor would be fucked.
Because of the lesser RON of normal ULP (between 88 and 92) your
Corolla may ping if you use this petrol, you may like to retard the
timing to about 5-6 degrees if this becomes a real problem. Or, you
could
use Premium Unleaded (usually 95 RON) or one of the brand name petrols
(BP Ultimate, Shell Optimax, etc) which have a RON of 98. Good fuel
like this will also make your car slightly more powerful, compared to
running a lesser fuel, so you'll get better mileage, or more power if
you're a leadfoot :) As higher octane fuel is slower burning, the
timing must be advanced to recognise a performance gain. On stock
motors, I run 12 degrees with BP Ultimate.
Theoretically, if you're running unleaded petrol, you're sposed to get
a catalytic converter installed in your exhaust system. Whatever.
Other Fuels
BP and Shell distributors sell a 100 RON fuel, which is usually around
$2/Litre. You could also run nice leaded Avgas if you like (and can get
your hands
on it).
LPG
There have been a few Corollas around running on LPG. I'm told this
stuff is really good for your motor both in the smooth running and the
way it doesn't pollute your oil. There are two basic designs of LPG
systems, you want to get the one with what's called an Air Gas Valve
Mixer, companies such as Impco and Gas Research make parts like this
for performance systems. LPG also has an advertised RON of 110, though
this seems to have dropped in recent years. If you can afford the
system (tank, lines, converter, mixer, piping) then go for it!
Octane Boosters
These formulations raise the RON level of your fuel, and are
designed for use in Unleaded. The only one that works more than 1 or 2
RON is one called "104+ Super" which is in a black bottle and about 32
bucks. There is a lesser formula of the same name, in a red bottle,
about 25 bucks. I can't see how they would be economically worthwhile
if
you're considering adding one every tank.
You can also buy drums of Methyl Benzine (also known as Tolulene) from
fuel distributors. The going price seems to be about $40/20L. Mix this
at a ratio of 1 part Tolulene to 7 parts Petrol. Wear really thick
protective gloves and a gasmask, this stuff is really carcinogenic (it
gives you cancer). If you run a richer Tolulene ratio, your motor will
go really hard but you'll burn out your valves and seats pretty
quick.